Wednesday, April 08, 2020

Aircraft Structural Failure: Hooley Jet Eze, N815EY; fatal accident occurred September 01, 2018 near Covington Municipal Airport (M04), Tipton County, Tennessee

    Overview of Internal Left Wing Structure. 


View of the Left and Right Wing (Right Wing Above left wing). 

Fragment of Wing as Found at the Accident Site. 

Main Wreckage at Jet Engine at the Accident Site. 

The sections of the upper wing skin and spar cap from the left wing, reconstructed in their relative positions prior to the accident.

The section of the wing skin and the upper spar cap sections, with the cap sections inverted and removed from their position on the wing skin.

View of the outboard side of the spar cap and wing skin pieces, reassembled.

With the spar cap segment removed and inverted in place.

View inboard, showing the cap segments and wing skin remnants.

View inboard, showing the cap segments and wing skin remnants.

The inboardmost area of the spar cap and wing skin segments, reassembled.

With the spar cap segment removed and inverted in place.

The upper surface of spar cap segment C.

The lower side of the spar cap segment C, showing intra-component fracture.

Spar cap section C upper face, showing a flat surface with the underlying woven structure of the spar cap composite.

Closer view of the spar cap section C surface.

Spar cap section C lower surface face, fractured fibers and resin fracture features.

Closer view of the spar cap section C lower surface, showing hackles and matrix fracture between fibers.

The lower surface of loose ply 5 at the spar cap location, showing “dry fiber” weave and globules of resin between the weave gaps.

Lower face of the ply 5, showing resin fracture away from the spar cap location.

The A/B section of the upper spar cap, looking outboard at the inboard section.

The A/B section of the upper spar cap, looking outboard with the inboard C section positioned to show the locations of the internal cracks and lower fracture surface.

Angled view of the underside of the inboard fracture of the spar cap C segment.

Angled view of the upper face of the inboard fracture of the spar cap C segment.

The upper surface of the inboard left wing skin, as received.

Closer view of the inboard area of the wing skin section, showing paint cracking and absence adjacent to the fracture. 

Overview of left-wing fragments, laid out after recovery from accident site.

Overview of Internal Left-Wing Skin. 

Overview of portion of left-wing spar cap.

Overview of portion of the left-wing upper and lower skin and wing spar.

Overview of Left Aileron.

Overview of right wing laid out after recovery from accident site.

Right Aileron.

Area Removed for Materials Lab Examination.

Lance Hooley
Lance Hooley, 59, of Kissimmee, Florida, passed away on  September 1st, 2018.  Lance was a captain with JetBlue Airways, a founding member of the Jet Guys of Covington and a U. S. Air Force Veteran. He is survived by his wife, Janet Hooley of Kissimmee.

The National Transportation Safety Board traveled to the scene of this accident.

Additional Participating Entity:

Federal Aviation Administration / Flight Standards District Office; Memphis, Tennessee

Aviation Accident Factual Report - National Transportation Safety Board: https://app.ntsb.gov/pdf


Investigation Docket - National Transportation Safety Board: https://dms.ntsb.gov/pubdms

https://registry.faa.gov/N815EY

Location: Covington, TN
Accident Number: ERA18FA240
Date & Time: 09/01/2018, 1720 CDT
Registration: N815EY
Aircraft: LANCE M HOOLEY JETEZ
Aircraft Damage: Destroyed
Defining Event: Aircraft structural failure
Injuries: 1 Fatal
Flight Conducted Under: Part 91: General Aviation - Personal 

On September 1, 2018, about 1720 central daylight time, an experimental amateur-built JETEZ airplane, N815EY, was destroyed after an in-flight breakup and a subsequent impact with terrain near Covington Municipal Airport (M04), Covington, Tennessee. The airline transport pilot was fatally injured. The airplane was owned by the pilot and operated as a Title 14 Code of Federal Regulations Part 91 personal flight. Visual meteorological conditions prevailed at the time of the accident, and no flight plan was filed for the local flight.

According to a witness who routinely observed the accident airplane's flights and was familiar with the airplane's design, the purpose of the flight was for the accident airplane and another canard jet airplane based at M04 to fly together. The witness reported that the accident airplane departed runway 19 before the other airplane, climbed to an altitude of about 1,000 ft above ground level (agl), and then started a 270° descending right turn. He also reported that the airplane crossed over the middle of M04 at an altitude of about 200 ft agl and an estimated speed of 200 to 210 knots and in a level pitch and bank attitude. He further reported that, shortly after the airplane crossed the runway, he observed the left wing and winglet "oscillate" about five times and that the left wing then "exploded."

This witness subsequently observed pieces of the airplane falling, the airplane abruptly pitching up about 90°, the right wing separating from the fuselage, and the airplane descending into a cotton field. He reported that the airplane's engine "sounded fine" throughout the flight. The witness provided an additional statement about 3 months after the accident, indicating that the airplane was traveling "at least 200 knots, it could have been 230 knots" just before the left wing failure.

According to another witness, who was an airline transport pilot, he observed the accident airplane cross over the airport at an altitude of about 200 ft agl. He stated the airplane's engine sounded as if it "was not at idle" and "had power." This witness continued watching the accident airplane after it flew over the airport and observed a "gentle pull-up" followed by a "wave like movement" or "wiggle" in the left wing, and then the "left wing failed at mid-span." Subsequently, the airplane pitched up "violently," the right wing "snapped off" in one piece, and several additional pieces departed the airplane as it "tumbled down to the left" and impacted terrain. He then observed fire and smoke. 

Pilot Information

Certificate: Airline Transport; Commercial
Age: 59, Male
Airplane Rating(s): Multi-engine Land; Single-engine Land
Seat Occupied: Front
Other Aircraft Rating(s): Balloon
Restraint Used: 5-point
Instrument Rating(s): Airplane
Second Pilot Present: No
Instructor Rating(s): Airplane Multi-engine; Airplane Single-engine
Toxicology Performed: Yes
Medical Certification: Class 1 Without Waivers/Limitations
Last FAA Medical Exam: 03/22/2018
Occupational Pilot: Yes
Last Flight Review or Equivalent:
Flight Time: (Estimated) 22000 hours (Total, all aircraft), 100 hours (Total, this make and model) 

According to Federal Aviation Administration (FAA) records, the pilot held an airline transport pilot certificate with an airplane multiengine land rating and a commercial pilot certificate with airplane single-engine land and lighter-than-air balloon ratings. He also held a flight instructor certificate for airplane single- and multiengine land; and type ratings for the Airbus A320, Jetstream BA-3100, Embraer EMB-120, and Saab SF-340; and a repairman experimental aircraft builder certificate for the accident airplane as well as the DR-107 experimental amateur-built airplane.

The pilot was issued an FAA first-class medical certificate dated March 22, 2018, with a limitation that required him to wear corrective lenses. At that time, the pilot reported 22,000 hours of total flight experience, including 5 hours during the preceding 6 months. The pilot's logbooks were not recovered. 

Aircraft and Owner/Operator Information

Aircraft Make: LANCE M HOOLEY
Registration: N815EY
Model/Series: JETEZ
Aircraft Category: Airplane
Year of Manufacture:
Amateur Built: Yes
Airworthiness Certificate: Experimental
Serial Number: 2009-815EY-1
Landing Gear Type: Retractable - Tricycle
Seats: 2
Date/Type of Last Inspection:  Unknown
Certified Max Gross Wt.: 3500 lbs
Time Since Last Inspection:
Engines: 1 Turbo Jet
Airframe Total Time: 100 Hours at time of accident
Engine Manufacturer:General Electric 
ELT: Not installed
Engine Model/Series: GE-T58-8B
Registered Owner: On file
Rated Power: 840 lbs
Operator: On file
Operating Certificate(s) Held: None 

According to FAA airworthiness records and publicly available information, the airplane was a two-seat, original-design, canard-style airplane manufactured by the pilot. The airplane was powered by a modified GE-T58-8B turbine engine, which was originally designed for a military helicopter. The airplane received a special airworthiness certificate on June 30, 2014. The witness who was familiar with the operation of the accident airplane reported that it had accumulated about 100 total hours of operation. The maintenance records and builder records were not located. Extensive online content described how the accident pilot designed, manufactured, and operated the airplane.

In May 2018, KITPLANES magazine published an article authored by the accident pilot that was titled, "JET EZE, Turning a Dream into Reality, Part 1 and 2." The article included a photograph of the accident airplane at an unknown date and time before the accident flight, as shown in figure 1.


Figure 1. Accident airplane.
(Source: KITPLANES magazine, May 2018.)

According to the article, the airplane was designed and manufactured over a 13-year period, with 11 years of "active building." The airplane had blended composite winglets in which a C-channel wing spar was extended to the tip of the winglets. The article stated that 5-ft peel ply was used in the composite layup process of the winglets. The article also stated that the canard was a "stock GU" design and that each wing contained two inner fuel pods and two outer baggage pods.

In February 2018, the accident pilot described the design, manufacture, and operation of the accident airplane in a narrated webinar titled "So, You Want to Build a Jet?" that was hosted by the Experimental Aircraft Association. A recording of the webinar appeared on the Jet Guys' YouTube channel (https://www.youtube.com/watch?v=_Izm3CGZDFo).

According to the "Jet Guys" website, they specialized in canard jet airframe modifications, repairs, powerplants, electrical modifications, and condition inspections. The owner and operator of Jet Guys was a witness to the accident (his account was provided first in this report). He was also the FAA designated airworthiness representative that signed off the airplane's special airworthiness certificate in 2014.

During the 1 hour 27-minute webinar, the pilot reported that the accident airplane had a Vne (never exceed airspeed) of 250 knots indicated airspeed (KIAS), or 310 knots true airspeed, and stated, "Have I been past that [airspeed]? Yeah, it was exciting, and I won't tell you how far I went past it." He explained that the airplane was "airframe limited" because the jet engine could propel the wings faster to loads that they could not tolerate. He also reported that the airplane's first flight was in 2017, although the airplane had received its FAA special airworthiness certificate in June 2014. 

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: M04, 280 ft msl
Distance from Accident Site: 0 Nautical Miles
Observation Time: 1715 CDT
Direction from Accident Site: 244°
Lowest Cloud Condition: Few / 5000 ft agl
Visibility:  10 Miles
Lowest Ceiling: None
Visibility (RVR):
Wind Speed/Gusts: 6 knots /
Turbulence Type Forecast/Actual: None / None
Wind Direction: 130°
Turbulence Severity Forecast/Actual: N/A / N/A
Altimeter Setting: 30.04 inches Hg
Temperature/Dew Point: 31°C / 23°C
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: Covington, TN (M04)
Type of Flight Plan Filed: None
Destination: Covington, TN (M04)
Type of Clearance: None
Departure Time: 1718 CDT
Type of Airspace: Class G

The weather conditions reported at M04 at 1715 included visibility of 10 statute miles, few clouds at 5,000 and 5,500 ft agl, wind from 130° at 6 knots, temperature 31°C, and dew point 23°C.

Airport Information

Airport: Covington Muni (M04)
Runway Surface Type: N/A
Airport Elevation: 280 ft
Runway Surface Condition:
Runway Used: N/A
IFR Approach: None
Runway Length/Width:
VFR Approach/Landing: None 

Wreckage and Impact Information

Crew Injuries: 1 Fatal
Aircraft Damage: Destroyed
Passenger Injuries: N/A
Aircraft Fire: On-Ground
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 1 Fatal
Latitude, Longitude: 35.586389, -89.578333 

The airplane's fuselage came to rest inverted in a flat cotton field about 0.5 nautical mile northeast of M04. The fuselage was oriented on a magnetic heading of 065°. The airplane sustained extensive impact damage, and evidence of a postimpact fire was observed. All major components of the airplane were accounted for along the airplane's debris path. Fragments of the outboard portion of the left wing and winglet were found separated from the left wing root about 1,000 ft from the fuselage. Fragments of the outboard portion of the right wing and winglet were found separated from the right wing root about 870 ft from the fuselage.

Flight control continuity could not be established from the control surfaces to the cockpit area because the flight control surfaces had separated from their attachments and the cockpit section was destroyed by the postcrash fire. Fragments of the canard were found separated from the fuselage in the debris path. The engine had separated from the engine mounts and was found with the fuselage. The engine was visually inspected, and no signs of foreign object debris damage were observed. The inlet variable guide vanes were intact and displayed rotational scoring.

Portions of the left wing upper skin plies displayed evidence of fiber material transfer from the lower wing skin. Portions of the left wing upper spar cap and upper skin had a glossy appearance with no apparent evidence of fiber material transfer. The left winglet skin panels showed evidence of fiber material transfer between the winglet skin and the winglet spar caps. After examination, the left and right wing components were laid out. Figure 2 shows the top and bottom portions of the left wing and left aileron.


Figure 2. Left and right wing fragments.

Further examination of portions from the internal left wing structure was performed by the NTSB Materials Laboratory in Washington, DC. This examination showed that the upper wing surfaces and the upper spar cap sections had areas that were consistent with a resin-starved or dry laminate. These areas were also consistent with an adhesive disbond between the respective faying surfaces. This adhesive disbond was consistent with a lack of impregnation and interfacial interaction of the resin into and with the glass fiber fabric, resulting in a lack of strong adhesion between the wing skin and the spar cap. These issues were consistent with a fabrication problem during manufacturing of the layup rather than wear over time or an environmental degradation failure. Reference the Materials Laboratory Factual Report in the public docket for additional details and photographs. 

Medical And Pathological Information

An autopsy of the pilot was performed by the Office of the Medical Examiner, West Tennessee Regional Forensic Center, Memphis, Tennessee. The pilot's cause of death was multiple blunt force injuries.

Toxicology testing performed at the FAA Forensic Science Laboratory identified salicylate (a metabolite of aspirin), acetaminophen (commonly marketed as Tylenol), amlodipine (blood pressure medication), and timolol (used orally to prevent recurrent heart attacks and as an eye drop for glaucoma) in the pilot's urine specimens. Amlodipine was found in the pilot's cavity blood specimens. None of the medications were considered impairing. The toxicology tests identified no carbon monoxide or ethanol in the pilot's cavity blood specimens. 

Additional Information

The witness who was the owner and operator of Jet Guys reported that, about 2 months after the accident airplane's first flight in 2017, a flutter event occurred with the accident airplane's left wing. The witness stated that he saw the flutter event on a video that the accident pilot had showed him. The video camera appeared to be mounted on the left wing, and the video of the flutter event showed the left winglet moving forward and aft, in a back-and-forth motion, about 4 inches and about one revolution per second. The witness thought that the airspeed during the flutter event was 232 KIAS. The witness reported that he was unaware of any structural repairs or modifications to the accident airplane after that flutter event.

12 comments:

  1. This failure is a cautionary tale for those who build or fly aircraft that rely on strength and integrity of hand-layup composite structures. The lack of resin impregnation (where the upper skin was supposed to bond to the spar) was never detected, resulting in failure and fatality in less than 100 hours of flight time on the aircraft.

    Commercial fabrication processes for composite structures include reliable methods of verification such as ultrasonic testing for voids, and coupon sample tests. It is notable that the tap test done after the first flutter event did not detect the dry/no bond area. Such testing can only find gross defects when performed by hand without test instrumentation.

    For this high performance aircraft project, achieving proper adhesive bonding of skins to spar was essential. A professional ultrasound assessment should have been done after fabrication (or after that first flutter event) to look for voids and detect lack of bonding in critical areas.

    An example (with illustrations):
    https://www.olympus-ims.com/en/applications/non-destructive-bond-testing-aircraft-composites/

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  2. They exceeded every parameter of this aircraft design, engineering and (more importantly) structural load a by a wide margin. Burt Rutan has to shaking his head in disgust.

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  3. This is a shocking and heartbreaking read.
    I went to the August 2017 Kit Planes article to try to understand how this type of accident could occur.
    Not having read this previously, my first impression was that of a snarky, almost arrogant type of interview.
    Back to the accident photos...
    The spar cap failure was not initially a de-laminate, The Spar was never properly laminated when the builders' lay up took place when constructed.
    Even the most junior aircraft mechanic, or boat manufacturer/repair, accomplishing a simple cowling or fiber glass wheel pant repair, understands the preparation, and wetting process to bond the next ply of fiberglass or peel ply for future strength/adhesion of subsequent plys.
    How did this spar ever pass a simple visual inspection when built? Who looked at this and decided the next ply was "OK" to overlay? Clearly, "they" did not understand this process.

    I have to believe the love and interest of aviation these guys have and time and money invested at all levels of construction and their research into the aircraft and its systems, would have not allowed this flaw to occur.
    Previous test flight video did show slight wing flutter or vibration...,
    Who determined that this was "acceptable" ?
    Why was there not an ultra-sonic inspection of the suspect components (Wing/Wingtip) accomplished?
    A sample control lay-up of a test spar section, clear of any de-laminate, voids, inclusions and properly bonded, would have been a valuable "base-line" test for comparing ultra sonic mapping Vs. the actual results from the aircraft spar. This would seem like a valuable troubleshooting tool to isolate the known wing flight issues.
    I admire the spirit, heart broken by the loss.

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  4. It is puzzling that both the top and bottom surfaces of that first ply of skin layup across the spar cap had dry areas (see discussion top of Pg. 3 in Materials Lab report).

    Application of resin and smoothing by spreader or roller forcing during hand layup will saturate through the fiberglass weave and produce a uniform translucent look across the worked area. One possible explanation for the lack of saturation underneath and dry weave on the upper surface of that first ply would be that the resin mix began to stiffen up (due to too long since mixed) and they stopped applying it.

    When they made up another batch of resin mix and continued layup, the obviously dry top surface areas should have been filled and smoothed before they laid on a second ply. Even if that was missed, soak thru during second ply work would wet dry areas on the top surface of the first ply.

    The photos show the lack of resin, but it is a mystery how the top surface of the first ply could have those dry areas, even if they were hurrying or had interruptions in between plies. What set of circumstances could produce the "dry both sides" areas found on the first ply in that upper wing skin?

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  5. what a terrifying final few seconds r.i.p.

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  6. Type A individual doing wet layups, perhaps he tried to wet more than one layer at a time.
    But those winglets! They are comically huge, 5 times bigger than necessary. Deficient spar workmanship trying to support Dumbo ears.

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    Replies
    1. Surely the winglets are that size since they're also rudders...

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  7. Leaving no margin for error. Regretfully, there are no old, bold pilots!

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  8. I wonder if exceeding the Vne (to which he did not say what speed it was) accelerated this failure and weak point. While it's clear that there was a serious point of lack of core bonding and a gap in the spar, how much longer would the aircraft have flown under normal ops with never exceeding Vne in the first place? A failure was inevitable, but did that Vne push aggravate the flaw to inevitable failure at <100 hours instead of say 250 or 500? We'll never know. What I do know is that this is exactly the reason I would never buy a home-built no no matter how experienced the builder is. I'll spend more on my life, the lives of my loved ones, and those innocents on the ground I'm flying over on a composite aircraft built from an actual mass manufacturer (like a used Cessa TTx).

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  9. Load factor, which increases with weight and speed found a flaw in manufacturing. Rutan cautioned, in very strong terms about flutter.

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  10. Sounds similar to the 1/2 scale Gripen that suffered fin flutter a while back, I bet it also had bonding issues!

    https://www.youtube.com/watch?v=8yf_QTbDeWM

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  11. Sadly... an accident waiting to happen...very sad, yes fortunately no one else was injured or killed

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